Changes

fix comment typos to cycle bots

DWARFDebugFrame.cpp - remove unused <string> include. NFCI.

MachOObjectFile.cpp - remove unused <string> include. NFCI.

RegUsageInfoPropagate.cpp - remove unused <string> and <map> includes. NFCI.

ProfiledCallGraph.h - remove unused <string> include. NFCI.

DetailedRecordsBackend.cpp - tidy implicit header dependencies. NFCI.

We don't use <algorithm>, <set> or <vector>, but we do use std::pair (<utility>).

DetailedRecordsBackend.cpp - printSectionHeading - avoid std::string creation/copies.

Don't create std::string from constant c-strings or pass std::string by value - we can use StringRef instead.

DIPrinter.h - tidy implicit header dependencies. NFCI.

We don't use <string> but we do use std::unique_ptr (<memory>) and llvm::Optional<>

BoundsChecking.cpp - tidy implicit header dependencies. NFCI.

We don't use <vector> but we do use std::pair (<utility>)

RawError.h - remove unused <string> include. NFCI.

[LoopUnroll] Test multi-exit runtime unrolling with predictable exit (NFC)

The (prior to prologue insertion) predictable exit shouldn't get
folded here. Make sure it isn't...

[lld/mac] clarify comment

This is a "we should do X in the future" fixme, not an "X might go wrong"
fixme.

DirectoryWatcher: also wait for the notifier thread

Ultimately the DirectoryWatcher is not ready until the notifier thread
is also active.  Failure to wait for the notifier thread may result in
loss of events.  While this is not catastrophic in practice, the tests
are sensitive to this as depending on the thread scheduler, the thread
may fail to being execution before the operations are completed by the
fixture.  Running this in a tight loop shows no regressions locally as
previously, but this failure mode was been sighted once on a builder.

[SPARC] Legalize truncation and extension between fp128 and half

Lower truncations and expansions between fp128 and half values into libcalls.
Expand truncating stores into two separate truncation and a store operations.

Reviewed By: jrtc27

Differential Revision: https://reviews.llvm.org/D104185

[clang-format] Adds a formatter for aligning arrays of structs

This adds a new formatter to arrange array of struct initializers into
neat columns.

Differential Revision: https://reviews.llvm.org/D101868

[fuzzer] Fix build on musl

cstddef is needed for size_t definition.
(Multiple headers can provide size_t but none of them exists.)

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D96213

[ELF] Add OVERWRITE_SECTIONS command

This implements https://sourceware.org/bugzilla/show_bug.cgi?id=26404

An `OVERWRITE_SECTIONS` command is a `SECTIONS` variant which contains several
output section descriptions. The output sections do not have specify an order.
Similar to `INSERT [BEFORE|AFTER]`, `LinkerScript::hasSectionsCommand` is not
set, so the built-in rules (see `docs/ELF/linker_script.rst`) still apply.
`OVERWRITE_SECTIONS` can be more convenient than `INSERT` because it does not
need an anchor section.

The initial syntax is intentionally narrow to facilitate backward compatible
extensions in the future. Symbol assignments cannot be used.

This feature is versatile. To list a few usage:

* Use `section : { KEEP(...) }` to retain input sections under GC
* Define encapsulation symbols (start/end) for an output section
* Use `section : ALIGN(...) : { ... }` to overalign an output section (similar to ld64 `-sectalign`)

When an output section is specified by both `OVERWRITE_SECTIONS` and
`INSERT`, `INSERT` is processed after overwrite sections. To make this work,
this patch changes `InsertCommand` to use name based matching instead of pointer
based matching. (This may cause a difference when `INSERT` moves one output
section more than once. Such duplicate commands should not be used in practice
(seems that in GNU ld the output sections may just disappear).)

A linker script can be used without -T/--script. The traditional `SECTIONS`
commands are concatenated, so a wrong rule can be more noticeable from the
section order. This feature if misused can be less noticeable, just like
`INSERT`.

Differential Revision: https://reviews.llvm.org/D103303

Introduce tensor.insert op to Tensor dialect.

Add `tensor.insert` op to make `tensor.extract`/`tensor.insert` work in pairs
for `scalar` domain. Like `subtensor`/`subtensor_insert` work in pairs in
`tensor` domain, and `vector.transfer_read`/`vector.transfer_write` work in
pairs in `vector` domain.

Reviewed By: silvas

Differential Revision: https://reviews.llvm.org/D104139